Lamp-socket.



Patented Nov. 5, 1912.

H. C. WIRT L F. W. SANFORD.

y LAMP SOCKET.

APPLICATION FILED JUNI: 22, 1909.

rain srafrns rarnivr HERBERT C. WIRT, 0F PLYMOUTH, MASSACHUSETTS, `ANDFRANKW. SANFORD, 0F

` CHICAGO, ILLINOIS.

LAMP-SOCKET.

Specification of Letters Patent.

Patented Nov. 5, MM2.

Application led June 22, 19Q8. Serial No. 439,705.

senting like parts.

This invention relates to lamp sockets and has for its objects toprovide a novel means` l is attached and which is electrically conforretaining the. cap to the shell of the socket and also to provide anovel manner of mounting the circuit terminals on the porcelain base. 4

In accordance with our invention the cap is held to the shell of thesocket by providing one of the parts on opposite sides with projectionsof uniform cross-sectional area throughout their length, whichprojections enter apertures in the other part. This construction notonly securely holds the tw'o parts together, but prevents one part fromturning on the other. The porcelain base of the socket is made in twosections, each of which is provided' with cavities or recesses havingsuch a relation to each other that when the sections are in position,suitable chambers are formed `for receiving `the switch mechanism andthe circuit terminals. Both the switch mechanism and the circuitterminals are mounted on.the lower section of the base and meansseparateffrom said terminals and switch mechanism is provided forsecuring the two sect-ions together.

The novel features wherein our invention resides will be morefully-hereinafter described and then pointed out in the appended claims.

Inpthe drawings wherein wehave illustrated one embodiment of ourinvention, Figure l is a side viewof a socket 'embodying the invention;Fig. 2 is an enlarged sec- -tional view on the line. :v -m, Fig. 1; Fig.3

hicago,vcounty of Cook, and State off Illinois, respectively, haveinvented an Im. provement in Lamp-qockets, of which thei followingdescription, in connection with; the accompanying drawing, isaspecification, like characters on the drawing repre-l section on linea-a, Fig. 4; Fig. 7 i's a sectional view of the cap and shell showingthe manner of removing the cap.

3 'is the shell of the socket and 4 the cap. thereof. Situated withinthe shell is the usual porcelain base which 4sustains the switchcontacts 5 and 6, the contact 5 being electrically connected with acircuit terminal 8 to which one of the conducting wires may be attached,and the contact 61 being electrically connected to the usual center lampterminal 9. `90 isv the second circuit terminal to which the otherconducting wire nected with the screw shell 91. These are the partswhich are commonly found in lamp sockets. y

One feature of our invention relates to the manner in'which the shelland the ca are secured together. In accordance wit this feature of theinvention, either the cap or the shell has extending therefrom on'oppcsite sides thereof projections 10 which are received in apertures11 formed in the other part. In the present embodiment of our inventionthe projections are carried by the shell and the apertures are formed inthe cap.

We prefer to make the projections 10 of Isubstantially uniform crosssectional area throughout their length and also to make them with allthesides thereof extendmg substantially, at right angles to the wall ofdrical as shown in the drawing, in which case the apertures 11 will havea corresponding shape. The shell is slightly larger than the porcelainbase so that it 1s ossible 4to portion of the porcelain base; Fig. 6 isa y press `the side of the shell inward y adjacent l either one of theprojections 10 suiiciently to withdraw the projection from the aperture11 and then to separate the cap and the shell at this side. Theprojections 10 eX- tend radially so that the side walls thereof areperpendicular to the shell and form square shoulders for engagement withthe walls of the apertures 11. As a result when the cap and the shellare locked together, it will beimpossible either to turn the cap withrelation to the shell or to separate the cap from the shell by alongitudinal movement without first pushing inwardly on the side of theshell adjacent the cap, as seen in Fig. 7, to withdraw the projectionfrom the aperture. These projections 10 ma be either formed bystrikingup Vthe material of the shell or may be in the form of pins or otherprojections secured to the shell.

, One advantage of our present construction is that the projections andapertures may be placed at any desired points on the shell and cap. Weprefer to place them opposite cach other, although this is not essentialto the invention. We prefer also to so place them that a line connectingthem extends at right angles to the key shaft 18. The advantage ot thisconstruction is .that the strain or twisting action produced by 'theturning of the key 19 will not tend to disconnect the shell from the capas might be the case if the projections were arranged in substantiallythe same plane as the key. The twisting strain to which the socket issubjected when the key is turned would tend to turn the shell relativeto the ca about the axis of the key, and it will be -o vious that l thisstrain can be much better resisted when vto the projections are placedat right angles to the axis of the key.

The procelain base which supports the Acircuit terminals and switchcontacts coinprises the two members 14 and 15 which are shown as beingclamped together when in operative position by means of a clamp- 'i'ngbolt 16 that passesthrough the two members. The key shaft 18 carries theusual switch cam 7 and is provided at its end with a thumb piece or key19. The shaft 18 is journaled in a bearing formed partly in each of thetwo members 14 and 15, said shaft being held in place between the twomeinbers when the latter are clamped together by the bolt 16.

One feature of our invention relates to the manner in which the contactsand terminals are supported and according to this feature both contactsand both terminals 8 and 90 are supported entirely on the lower member14 of the porcelain base. The member 14 is provided with the recess20'in which the contacts are partially' received, and the member 15'isprovided with an alined recess 21 which when the two members 14 and 15are together forms with the recess 2O a cavity to receive both theswitch contacts 5 and 6, as clearly seen in Fig. 2. The contact 6 isformed from a strip which is bent into V-shape and one arm of Which'isprovided with the foot 40 which rests on the bottom of the recess 20 andthrough which the lamp terminal or stud 9 passes, said foot being heldfrml in placeby the head 41 formed on or app ied to the stud.

The contact 5 is held in position by a incasso clamping screw 24 whichenters the member 14 from the bottom, as seen in Fig. 2, and the' samescrew 24 screws into4 the terminal 8 and secures it in place.

IThe cap portion 15 of the porcelain base is provided with a side recess26 in which the terminal 8 is received and in which the conducting wireleading to thev terminal 8 is also received. This side recess 26 leadsinto and connects with the 'recess or cavity 21 and the cap member 15 ispre-ferably made with a notch 44 to receive the upper end of theterminal 8, (see Fig. 2).

The terminal 90 is secured to the lower portion 14 of the porcelain baseby a suitable screw 93 .(see Fig. 6) which passes through the screwshell 91 and thus electrically connects said terminal to the shell aswell as securing the-terminal to the part 14 of the porcelain base. Thecap portion 15 of the orcelain base is made with the recess 27 in whichthe terminal 90 is received. v

It will thus be seen that all the securing means for the terminals andcontacts are located in the section 14 of the porcelain base and thatthe cap portion 15 can be re moved without disturbing any of thesesecuring means.- It is possible, therefore, to remove the cap 4 and thento remove the clamping bolt 16 and the cap portion 15 of the porcelainbase thereby to gain access to the terminals and the contacts withoutdisturbing any of the devices used to secure said terminals andcontacts'in their proper position.

Having fully described our invention, what we claim as new and desire tosecure by Letters Patent is A 1. In a lamp socket, the combination witha shell, of a cap, and means foi-,securing the cap and shell togethercomprising two radially-extending projections rigid .with one of saidparts, the other art having apertures toreceivesaid projections, eachprojection having its side walls perpendicular to the walls of the part'from which it extends and the walls of said parts adjacent one of saidprojections being capable of radial movement relative to each other topermit engagement and disengagement of the projections with theapertures, the perpendicular side walls of the projections preventingturning movement of the parts relative to each other.

2. In aA lamp socket, the combination with a shell having ri idtherewith two oppositely-disposed cy indrical projections, the wall ofthe lamp socket adjacent one of the projections being capable of beingpressed inwardly, of a cap for the socket, the portion of the cap whichembraces the socket being imperforate except for two apertures adapt edto receive the projections.'

3. 1n a lamp socket, the combination with a shell having rigid therewithtwo opponames to this specication in the presence sitfleily-diposedcyllidricil progections, ang of two subscribing Witnesses. a e s otsituate mi Wa etween sai v projejctions, of a cap Afor they shell, thepor 5 tion 'of the cap which embraces the shell being imperforate exceptfor two apertures Witnesses: which receive said projections. v LOUIS C.SMITH,

In testimony whereof we have signed our THOMAS J. DRUMMOND.

